(19)

(11)

EP 0 060 263 A1

(12)

(43) Date of publication: 22.09.1982 Bulletin 1982/38 (21) Application number: 81902532.0 (22) Date of filing: 02.09.1981

(51) International Patent Classification (IPC):  G03B 27/ 73( . ) (86) International application number: PCT/US1981/001178 (87) International publication number: WO 1982/001082 (01.04.1982 Gazette 1982/09)

(84) Designated Contracting States: DE (30) Priority: 11.09.1980 US 19800186189 (71) Applicant: PAKO CORPORATION Minneapolis, MN 55440 (US)	(72) Inventor: STEWART, James F. Shoreview, MN 55112 (US)